Non-relativistic heterotic string theory

In this work we consider heterotic-gravity as the low-energy approximation to heterotic string theory. We define a consistent non-relativistic limit of heterotic gravity that includes the Yang-Mills Chern-Simons term. We perform three tests on the heterotic limit: we use it to (i) derive the non-relativistic transformation rules, (ii) show the existence of a finite non-relativistic heterotic action and (iii) obtain the longitudinal non-relativistic T-duality rules. We show that in all these cases the limit procedure is well defined, free of divergences and leads to consistent non-trivial results. We comment on the interpretation of the T-duality rules in terms of a heterotic non-relativistic geometry underlying non-relativistic heterotic string theory.